A floor structure in vehicle body rear part has been conventionally known in which a step part is formed between a main floor panel and a rear floor panel of a vehicle cabin. A cross member extending in a vehicle width direction is arranged at a position of the step part so as to enhance the floor strength.
Patent Document 1 discloses a structure in which two cross members makes a joint in a step part between a main floor panel and a rear floor panel. In Patent Document 1, a front cross member and a rear cross member are combined to form a closed cross section, and the members having the closed cross section connect the main floor panel and the rear floor panel.
In another example, Patent Document 2 discloses a structure in which cross members bent in center portions thereof in the vehicle width direction are arranged in a step part between a main floor panel and a rear floor panel.